454 vs 502 flywheel
 

Is there any difference between the 454 mark IV flywheel and the 502 gen 6 flywheel? As far as I know the 454 and 502 flywheels are the same, but I'm not sure if they interchange between the mark IV and gen 6. I know they bolt up, but is the balancing aspect of it the same?

Thanks,
Frank

Was the 454 a Mag? If it wasn't then no the flywheels cannot be interchanged.

Yes 454 Mag with steel crank.

Just because its a mag make no difference at all. Yes a MarkIV 454 and 502 are interchangeable.
The Mark IV is a two piece seal and the gen 6 is a one piece.
I just made the mistake when I bought a gen 6flywheel for a MarkIV. I ended up throwing it in the scrap bucket and I just machined a 400 flywheel for a 454 MarkIV. The counter weights had to milled off.

They are both externally balanced right?

The Mag 454 had forged internals, the non mag 454 had cast internals unless I am wrong. The flywheel off of a 454 with cast internals cannot be used on a 502.

So as long as they are both Mag's with steel cranks, they are interchangable right?

Thanks,
Frank

I am pretty sure. I will check Dennis Moore's book tonight. He has a couple pages explaining what is interchangebale.

Steel cranks and cast cranks are the same for Mark IV engines.

Yes they are both be external balance.

The 396, 402 and 427 where internal balanced engines.

I assumed you where going to have the flywheel balanced with the rest of the engine components? Or do you plan to just replace the one you currently have?

Is there any difference between the 454 mark IV flywheel and the 502 gen 6 flywheel?

I just reread your original post. Are you asking if a Gen 6 flywheel will fit on a MarkIV? If so, NO it will not work without machine work. The had additional weight added when they went to the one piece seal.
Hope this clears things up.

I can't put my hands on my Dennis Moore Book but here is a link I found........

http://www.offshoreonly.com/forums/s...+454+Flywheels

i know where 2 454 mark IV flywheels are:D.....had to buy new ones when i went from 454 merc 420hps to 502s

I'd balance the complete rotating assembly. I've seen rods off by as much 10 - 15 grams and sometimes even more. Had one last week.
Just my .02

even though the gen IV and Gen VI flywheels look the same, and will bolt up with no issues you will end up with a vibration doiing this..I found out the hard way...what they did on the gen V, VI was ad more wieght to the flywheel to make uo for what they took away from the crank flange to use the one peice rear main seal..Rob